“Please bow your heads and close your eyes.”
For all of their bluster, fundamentalists are a private bunch when it comes to something as dearly personal as raising ones hand to give a non-specific response at the end of a sermon on a generic topic. There have to be some boundaries of personal space after all.
The anonymous hand-raising also gives the speaker the chance to speak “evangelistically” about the number of respondents. Not that most pastors would out and out lie but they might just claim to “see hands all over his room” when in fact exactly three people out two hundred have raised their hand and one of them is only eighteen months old.
Stand up, stand up for Jesus! Unless you’re making a decision at the end of the service. Then the protocol is “every head bowed, every eye closed, nobody looking around.”